. . . By daylight the doctors dealt successfully with these disadvantages, and Slateford, so to speak, 'made cheerful conversation'.
But by night they lost control and the hospital became sepulchral and oppressive with saturations of war experience. One lay awake and listened to feet padding along passages which smelt of stale cigarette smoke; for the nurses couldn't prevent insomnia-ridden officers from smoking half the night in their bedrooms, though the locks had been removed from all doors. One became conscious that the place was full of men whose slumbers were morbid and terrifying - men muttering uneasily or suddenly crying out in their sleep. Around me was that underworld of dreams haunted by submerged memories of warfare and its intolerable shocks and self-lacerating failures to achieve the impossible.
By daylight each mind was a sort of aquarium for the psychopath1 to study. In the daytime, sitting in a sunny room, a man could discuss his psycho-neurotic symptoms with his doctor, who could diagnose phobias and conflicts and formulate them in scientific terminology. Significant dreams could be noted down, and Rivers could try to remove repressions. But by night each man was back in his doomed sector of a horror-stricken Front Line, where the panic and stampede of some ghastly experience was re-enacted among the livid faces of the dead. No doctor could save him then, when he become the lonely victim of his dream disasters and delusions.
Shell-shock.2 How many a brief bombardment had its long-delayed after-effect in the minds of these survivors, many of whom had looked at their companions and laughed while inferno did its best to destroy them. Not then was their evil hour, but now; now, in the sweating suffocation of nightmare, in paralysis of limbs, in the stammering of dislocated speech. Worst of all, in the disintegration of those qualities through which they had been so gallant and selfless and uncomplaining - this, in the finer types of men, was the unspeakable tragedy of shell-shock; it was in this that their humanity had been outraged by those explosives which were sanctioned and glorified by the Churches; it was thus that their self-sacrifice was mocked and maltreated - they, who in the name of righteousness had been sent out to main and slaughter their fellow men. In the name of civilization these soldiers had been martyred, and it remained for civilization to prove that their martyrdom wasn't a dirty swindle.
-- Siegfied Sassoon, Sherston's Progress, writing about survivors of WWI
2 post-traumatic stress disorder